Cam wedge power clamp

ABSTRACT

A power-actuated clamp used for holding workpieces in a fixed position having reversible parts for simplified construction.

United States Patent [50] Field of Search 269/32, 94. 233

[56] References Cited UNITED STATES PATENTS 3,362,703 1/1968 Blatt269/233 Primary E.mminer-William S. Lawson mummy-Cullen, Settle, Sloman& Cantor ABSTRACT: A power-actuated clamp used for holding workpieces ina fixed position having reversible parts for simplified construction.

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mvsmon LELAND F. BLATT ATTORNEYS CAM WEDGE POWER CLAMP BACKGROUND OF THEINVENTION l. Field of the Invention This invention relates to acylinder-operated power clamp having a body section comprising twoidentical parts which enables the clamp to be simply and economicallymanufactured.

2. The Prior Art Various power clamps are known in the art. The clampsin general have a cast body section used in securing the clamp arm.These body sections are in general one piece.

It is an object of this invention to provide a new and improved powerclamp having a body section of two identical and interchangeable parts.

Other objects and advantages of this invention will become apparent fromthe following specification when considered in conjunction with theaccompanying drawings, in which:

FIG. 1 is a plan view of the power clamp of this invention;

FIG. 2 is a side elevational view of the clamp of FIG. 1;

FIG. 3 is a sectional view in the direction of arrows 3-3 FIG. 2;

FIG. 4 is a side elevational view ofa body member forming a part of thepower clamp of this invention; and

FIG. 5 is a side elevational view of an alternative embodiment of theclamp of the invention, with parts shown in phantom.

Referring now to the drawings, the power clamp of this inventioncomprises a body 12 which comprises two identical members 14 and 16which abut each other on a common side. Each member 14 or 16 comprises abase plate 18 having a vertically extending rib 20 at one end, andanother vertically extending rib 22 at an intermediate location. Ahorizontally extending rib 24 extends the length of the base plate 18between the vertically extending ribs 20 and 22, and also along the restof the plate. The base plate 18 has bores 26 in the top and bottom inthe included areas defined by the ribs 20, 22 and 24 and thehorizontally extending rib 24 has vertical bores 28 in it through thatsection limited by the ribs 20 and 22. The bores 26 and 28 are means bywhich the body 12 can be attached to a support, i.e., screws or boltscan be inserted through the bores 26 or 28 into a support structure, notshown. Further to the right on the base plate 18, as seen in FIGS. 2 and4, are a pair of horizontally extending vertically aligned bores 30, oneon each side of the rib 24. The rib 24 has opposed arcuate recesses 32adjacent the bores 30.

The inward side of the base plate 18 is offset from a point coincidingwith the rib 22, on to the right end of the plate 18, as seen in FIG. 1,forming a recess 34. The inner face of the plate 18 defines a guide slot36. The guide slot 36 merges into a semicylindrical longitudinal bore 38as the rear of the plate 18 is approached. The opposed plates 18 form alongitudinal bore from the semicylindrical bores 38 when they abut eachother.

A power cylinder 40 is secured to one end of the body by means of boltswhich extend through the ribs 20. Thus, each body member 14 and 16 isfastened to the power cylinder 40, The power cylinder 40 may be either ahydraulically or pneumatically operated piston or solenoid.

A clamp arm 44 having a pivot bore 45 is pivotally mounted on body 12 bypivot bolt 46. Clamp arm 44 is illustrated without any particularfixture at its upper end portion, it being understood that theparticular fixture used in conjunction with this assembly does not forma part of this invention.

A roller cam 48 rides in a follower slot 50 formed in the clamp arm 44.The roller cam 48 is carried by an axle 52 secured to the opposed armsofa clevis 54.

Clevis 54 is in turn rigidly connected to end of piston rod 56, and ismounted for reciprocating movement within the guide slots 36 formed inthe opposed inner faces of the base plates 18 of body 12. A pair ofbronze elongated blocks 58 for the axle 52 are slidably mounted at theouter ends of axle 52. The guide blocks 58 are seated in the slots 36and provide smooth and easy reciprocating of clevis 54in body 12.

In operation, actuation of the power cylinder 40 upon a predeterminedsignal causes leftward movement of piston rod 56 and clevis 54 from theposition shown in the figures. This in turn causes roller cam 48 to movetoward the left end of follower slot 50.

The follower slot 50 is inclined relative to the axis of reciprocationof the clamp arm 44. Because of the inclination of slot 50 with respectto the axis of reciprocation, clamp arm 44 is forced to pivot clockwiseabout bolt 46, as viewed in FIG. 2. A subsequent actuation of powercylinder 40 causes the process to be repeated in the reverse direction,with clamp arm 44 pivoting counterclockwise about bolt 46 until it is inthe position shown in the figures.

It will be apparent that the power clamp of this invention provides asimple linkage with a minimum of moving parts while creating a highmechanical advantage. Clamp arm 44 is dimensioned relative to therecesses between the opposing portions of body members 14 and 16 toprovide substantially no space between the side faces of the arm and theinner opposed faces of the body members, so as to eliminate thepossibility of foreign matter and debris entering and fouling themechanism. Furthermore, the positioning of the roller cam between theclevis legs and the positioning of the guide blocks outside the clevislegs provides an extremely rigid assembly.

While as shown in the figures the clamp arm 44 is pivotable from ahorizontal to an upwardly vertical position, it can also be pivoted froma horizontal to a downwardly vertical position. This is accomplished bysimply reversing the arm and pivoting it about the lower of thevertically aligned bores 30.

. Thus, it is apparent that the two members 14 and 16 areinterchangeable and they also allow a clamp arm to be pivoted from ahorizontal to an upwardly vertical direction or from a horizontal to alower vertical direction without modification of the body component.

In an alternative embodiment, as seen in FIG. 5, the clamp arm 44 ispivotably connected at the base thereof to the clevis 54 by means of theaxle 52 extending through the clevis 54 and pivot bore 45 of theclamping arm 44. A pivot bolt 46 extends between the lower orifices 30and through the follower slot 50 of the clamp arm 44. A cam roller 60 isconfined within the follower slot 50. This allows the clamp arm 44 tohave both a reciprocal movement imparted by the piston rod 56 of thepower cylinder and a rotational movement around the pivot bolt 46extending through the orifices 30. Thus, clamping force is imparted byretracting the arm 44 by means of the clevis 54. When an attachment A ismounted on the end of the clamping arm 44, and the arm 44 issimultaneously retracted and pivoted, the object 0 being clamped, issqueezed between the attachment A and a support fixture F.

I claim:

1. A clamp comprising a body section comprising a pair of reversiblyinterchangeable substantially identical abutting body members, each ofwhich has a pair of vertically aligned pivot holes for pivotablymounting a clamping arm between opposed body members, said pivot holesof opposed body members being axially aligned, said body membersdefining a longitudinal bore, there being formed upon the interior ofsaid body members a pair of enclosed inwardly opening body groove trackscommunicating with said bore, means for mounting said body members on asupport structure, a clevis mounted for reciprocating motion in saidbore and having spaced legs, means for reciprocating said clevis, anaxle trans-- versely connecting said legs and provided with guide blockson the outer ends thereof slidable in said body groove tracks, aclamping arm having a pivot bore and a follower slot offset and inclinedfrom the axis of said longitudinal bore, mounted for pivotal movementbetween opposed portions of the body, said axle being confined withinsaid slot or said pivot bore, and, wherein, said axle extends throughsaid pivot bore, a pin extends through an opposed pair of said pivotholes and said follower slot, and a cam roller is situated within saidfollower slot and around said pin; whereby reciprocation of said cleviscauses said clamping arm to simultaneously pivot and linearly extend orretract along the axis of said bore.

1. A clamp comprising a body section comprising a pair of reversiblyinterchangeable substantially identical abutting body members, each ofwhich has a pair of vertically aligned pivot holes for pivotablymounting a clamping arm between opposed body members, said pivot holesof opposed body members being axially aligned, said body membersdefining a longitudinal bore, there being formed upon the interior ofsaid body members a pair of enclosed inwardly opening body groove trackscommunicating with said bore, means for mounting said body members on asupport structure, a clevis mounted for reciprocating motion in saidbore and having spaced legs, means for reciprocating said clevis, anaxle transversely connecting said legs and provided with guide blocks onthe outer ends thereof slidable in said body groove tracks, a clampingarm having a pivot bore and a follower slot offset and inclined from theaxis of said longitudinal bore, mounted for pivotal movement betweenopposed portions of the body, said axle being confined within said slotor said pivot bore, and, wherein, said axle extends through said pivotbore, a pin extends through an opposed pair of said pivot holes and saidfollower slot, and a cam roller is situated within said follower slotand around said pin; whereby reciprocation of said clevis causes saidclamping arm to simultaneously pivot and linearly extend or retractalong the axis of said bore.